1704240

Appears in sequences

• G.f.: A(x) = F(x*F(x)) where F(x) = 1 + x*F(x)^3 is the g.f. of A001764.at n=9A153291
• Sum of the divisors of 7^n-1.at n=6A366634
• a(n) is the sum of the divisors of n^n-1.at n=5A366819